Cover For Tissue Penetrating Device With Integrated Magnets And Magnetic Shielding

ABSTRACT

A cover for magnetizing a shaft of a tissue-penetrating medical device is disclosed including a sleeve member having a hollow body to form a protective closure over the shaft of the tissue-penetrating medical device. The proximal end of the hollow body provides a receiving space for receiving the shaft of the tissue-penetrating medical device. One or more magnet is disposed on the sleeve member. A magnetic shield composed of one or more shielding materials associated with the cover that minimizes any effects to the clinical environment from magnetic fields generated within the cover. Medical devices, assemblies and methods of magnetizing the shaft of a tissue-penetrating medical device using the cover are also disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/040,991, filed on Jul. 20, 2018, which is a continuation of U.S.patent application Ser. No. 15/251,637, filed on Aug. 30, 2016, issuedas U.S. Pat. No. 10,032,552 on Jul. 24, 2018, the disclosure of which isincorporated herein by reference in its entirety.

TECHNICAL FIELD

Aspects of the present disclosure relate to a cover for passivelymagnetizing a tissue-penetrating medical device to enhance visualizationduring an invasive procedure when used with a procedural guidance systemthat utilizes magnetic sensors to locate and project the position offeatures on the tissue-penetrating medical device relative to targetedanatomy, while shielding the clinical environment and equipment fromexposure to the magnetic field generated within the cover.

BACKGROUND

Traditionally, penetration of an invasive medical device such as aneedle and catheter tubing through skin tissue to reach the vein duringcatheter insertion is invisible to clinicians. For this reason,clinicians must rely on their first-hand experience with needleinsertion in combination with tactile sense to successfully identify thelocation of the vein. This may be a difficult task when attempting toaccess a small vein in a deep location under the skin, therebyincreasing the risk of excess pain and/or injury to the patient. Thereare similar problems with insertion of other invasive medical devicessuch as guidewires, catheters, introducer needles, stylets, scalpel andguidewire with respect to the inability to precisely visualize thelocation of the invasive medical device.

Emerging procedural guidance systems utilize a combination of ultrasoundand magnetic technologies to provide visualization of subdermal anatomyand device position in the in-plane and out-of-plane orientations. Thiscombination of ultrasound and magnetic methods also allows for theprojection or anticipation of the insertion device position relative tothe patient's anatomy, and thereby improves the likelihood ofsuccessfully accessing the vascular and completing the invasiveprocedure. The ultra-sound and magnetic procedural guidance systemtechnology requires that the invasive device have a sufficient magneticfield source that is maintained throughout the procedure.

In some current needle guidance systems, a magnetic field is generatedjust prior to insertion of the needle by magnetizing the needle byburying the metal cannula of the needle into a separate external needlemagnetizer until the point of the needle hits a rubber stopping surface.FIG. 1 shows a perspective view of a currently available separateexternal needle magnetizer 11. As shown in FIG. 1, current practice usesan unprotected needle 13 that is placed within the separate externalneedle magnetizer 11 to a depth defined by the bottom of the magnetizer.The current devices for magnetizing a needle prior to insertiongenerally are not sterile and are not disposable.

In systems of the type shown in FIG. 1, damage to the needle can occurthat is not apparent to the user that can negatively affect theinsertion process. Also, the step of the user actively magnetizing themetal cannula has some limitations and inherent risks as this approachdoes not guarantee consistent magnetization since variability inclinician procedures such as depth of insertion, speed of process, andcentering of the needle in the magnetizer will result in differentdegrees of magnetization. Considering the potential inconsistency of auser fully inserting the needle to the bottom of the magnetizer 11, thesignificant risk of damaging the needle tip, and the increased potentialfor contamination during this step, it would be advantageous to have asystem that passively and consistently magnetizes the needle withoutintroducing the aforementioned additional risks, such as needle tipdamage and increased potential for contamination.

Thus, there is a need for a system that passively and consistentlymagnetizes invasive medical devices thereby reducing or eliminatingrisks, such as needle tip damage and needle contamination whileproviding magnetic shielding to minimizing any effects to the clinicalenvironment from magnetic fields generated within the cover.

SUMMARY

An aspect of the disclosure pertains to a cover for both magnetizing atissue-penetrating medical device and providing a magnetic shielding toprotect the magnetic charge on the device. A first embodiment pertainsto a cover comprising a sleeve member having a hollow body, the hollowbody having an exterior surface, an interior surface, a distal end and aproximal end to form a protective closure over a portion (e.g., a shaft)of a tissue-penetrating medical device, one or more magnets disposedalong the sleeve member effective to magnetize a portion of atissue-penetrating medical device, and a magnetic shield composed of oneor more shielding materials that minimizes exposure of the clinicalenvironment from magnetic fields generated from the one or more magnetsdisposed along the sleeve member and the magnetized portion of atissue-penetrating medical device. In one or more embodiments, thesleeve member may have a length to cover the shaft of thetissue-penetrating medical device, and there are one or more magnetsdisposed inside the sleeve member. In one or more embodiments, themagnetic shield composed of one or more shielding materials surroundsthe one or more magnets disposed inside the sleeve member. In one ormore embodiments, the open end of the hollow tubular body provides areceiving space for receiving at least a portion (e.g., the shaft) ofthe tissue-penetrating medical device.

In one or more embodiments, the one or more magnets are fixed permanentmagnets. In an alternate embodiment, the one or more magnets include amagnetic collar.

In one or more embodiments, the device-receiving space permits movementof the tissue-penetrating medical device into and out of thedevice-receiving space. In one or more embodiments, the device-receivingspace permits movement of the tissue-penetrating medical device in aparallel direction to the longitudinal axis of the tissue-penetratingmedical device.

According to one or more embodiments, the two or more magnets aredisposed in slots positioned around the sleeve member. In one or moreembodiments, the slots positioned around the sleeve member surround thedevice-receiving space. In one or more embodiments, the magnetic shieldcomposed of one or more shielding materials surrounds a portion of theone or more magnets disposed inside the sleeve member. In one or moreembodiments, the magnetic shield composed of one or more shieldingmaterials surrounds the exterior surface of the sleeve member. In one ormore embodiments, the a magnetic shield composed of one or moreshielding materials surrounds the interior surface of the sleeve suchthat the one or more magnets disposed inside the sleeve member areexposed to the receiving space of the sleeve member.

In one embodiment, the shielding material may be a highly conductivematerial such as copper.

In another embodiment, the shielding material has a high magneticpermeability. The high magnetic permeability shielding material may bean alloy of nickel and iron metals. In a specific embodiment, theshielding material includes a ferromagnetic metal coating.

In yet another embodiment, the shielding material includes both a highlyconductive material and a ferromagnetic metal coating. The highlyconductive material may be copper and the high magnetic permeabilityshielding material may be an alloy of nickel and iron metals.

In one or more embodiments, the cover of the needle subassembly is inthe form of a needle cover, catheter packaging or shipping container.

In one or more embodiments, the shielding material may be spray-coatedonto an interior surface or exterior surface of the cover. In anotherembodiment, the shielding material may be spray-coated onto an interiorsurface and exterior surface of the cover.

In yet another embodiment, the magnetic shield composed of one or moreshielding materials may be insert-molded into the cover.

In one or more embodiments, the tissue-penetrating medical device may bea needle, cannula, stylet, catheter, scalpel or guidewire. According toone more embodiments, the cover passively magnetizes thetissue-penetrating medical device upon removal of the tissue-penetratingmedical device from the cover.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of a prior art disposable needlemagnetizer;

FIG. 2A shows a perspective view of an embodiment of a needle coverhaving a magnetic shield of the present disclosure;

FIG. 2B shows a perspective view of an embodiment of a needle coverhaving a magnetic shield of the present disclosure;

FIG. 3A shows an embodiment of a tissue-penetrating medical device priorto insertion into a needle cover having a magnetic shield of the presentdisclosure;

FIG. 3B shows an embodiment of a tissue-penetrating medical devicepartially inserted into a needle cover having a magnetic shield of thepresent disclosure;

FIG. 3C shows an embodiment of a tissue-penetrating medical device fullyinserted into a needle cover having a magnetic shield of the presentdisclosure;

FIG. 4 shows an embodiment of a tissue-penetrating medical device fullymagnetized after being removed from a needle cover having a magneticshield of the present disclosure;

FIG. 5 shows an embodiment of a tissue-penetrating medical device with amagnetic collar having a magnetic shield;

FIG. 6A shows a partial perspective view of a tip of a needle cover withan embedded magnet and a magnetic shield of the present disclosure;

FIG. 6B shows an end view of a needle cover with one embedded magnet anda magnetic shield of the present disclosure;

FIG. 6C shows an end view of a needle cover with two embedded magnetsand a magnetic shield of the present disclosure;

FIG. 7 shows an embodiment of a medical device with a cover having amagnetic shield of the present disclosure; and

FIG. 8 shows a partial exploded view of the embodiment of a medicaldevice shown in FIG. 7 having a magnetic field contained within thecover having a magnetic shield.

DETAILED DESCRIPTION

Before describing several exemplary embodiments of the disclosure, it isto be understood that the description provided is not limited to thedetails of construction or process steps set forth in the followingdescription. The devices and methods described herein are capable ofother embodiments and of being practiced or being carried out in variousways.

In this disclosure, a convention is followed wherein the distal end ofthe device is the end closest to a patient and the proximal end of thedevice is the end away from the patient and closest to a practitioner.

Aspects of the disclosure pertain to a cover of a tissue-penetratingmedical device with one or more magnets for passively magnetizing aportion of the tissue-penetrating medical device and a magnetic shieldcomposed of one or more shielding materials associated with the coverthat minimizes exposure of the clinical environment from magnetic fieldsgenerated from one or more magnets disposed within the cover and themagnetized portion of a tissue-penetrating medical device. The magneticshield composed of one or more shielding materials also minimizes anyadverse effects caused from exposure of the clinical environment to oneor more permanent magnets disposed within the cover. Aspects of thedisclosure pertain to an improved system that addresses the challengesto the existing technology and systems to passively magnetize aninvasive medical device, such as a needle used with a peripheralintravenous (IV) catheter, while providing magnetic shielding tominimizing any effects to the clinical environment from magnetic fieldsgenerated within the cover from one or more permanent magnet disposed inthe cover and the magnetized portion of the tissue-penetrating medicaldevice.

One or more embodiments of the present disclosure relate to a cover fora tissue-penetrating medical device, the cover having an integratedmagnet on or within the cover and a magnetic shield composed of one ormore shielding materials associated with the cover that minimizes anyadverse effects to the clinical environment from magnetic fieldsgenerated within the cover. According to one or more embodiments, thecover of the present disclosure passively and consistently magnetizes aportion (e.g., a shaft) of a tissue-penetrating medical device. In oneor more embodiments, passive magnetization of the tissue-penetratingmedical device is achieved with no additional or new clinical stepsbecause the invasive medical device already includes a cover that coversthe distal tip of the device. In one or more embodiments, the devicesand systems described herein provide more precise control of thelocation of the magnet relative to the device to be magnetized,resulting in a more consistent and predictable magnetic field applied tothe invasive medical device. In one or more embodiments, the devices andmethods described herein create no additional risk of needle damage andpose no additional risk for contamination when compared to existingmagnetizer devices.

Referring now to FIGS. 2A and 2B, one embodiment of a cover 12 of thepresent disclosure is shown for magnetizing a tissue-penetrating medicaldevice 10, the cover 12 comprising a sleeve member 14 having a hollowbody 20 having a distal end 21 and an open proximal end 22 to form aprotective closure over a shaft 34 of a tissue-penetrating medicaldevice 30, the cover having one or more magnets 50, and a magneticshield 60 associated with the cover 12. In one or more embodiments,distal end 21 may be closed or open. In one or more embodiments, themagnetic shield 60 minimizes any effects to the clinical environmentfrom magnetic fields generated within the cover from the one or moremagnets disposed within the cover and/or from a magnetized portion ofthe tissue-penetrating medical device 10. In one or more embodiments,the magnetic shield 60 isolates the magnetized region of thetissue-penetrating medical device 50 from any external magnetic andelectromagnetic fields thus keep the integrity of the magnetization ofthe magnetized region. In one or more embodiments, as shown in FIG. 5,the magnetic shield 60 contains the magnetic field generated by themagnetized region within the confines of the cover 12 to prevent themagnetized tissue-penetrating medical device 10 from causing magneticinterferences to sensitive equipment and devices in a hospital setting.The magnetic shield 60 would consist of one or more shielding materialwhich would enclose the magnetized region.

In one or more embodiments, the hollow body 20 can be tubular or anyother suitable shape. In the embodiment shown, the tissue-penetratingmedical device 30 is shown as a needle assembly including a needlehousing 32 and a shaft 34 of the needle having a sharp distal tip 36. Itwill be appreciated that in FIGS. 2A and 2B, the sleeve member 14 isshown as transparent and the shaft 34 of the tissue-penetrating medicaldevice 30 is visible. The sleeve member 14 has a length L that coversthe shaft 34 of the tissue-penetrating medical device 30, including thesharp distal tip 36 to prevent accidental needle sticks. The arrowsshown in FIG. 2 with respect to the length “L” also show thelongitudinal axis of the shaft 34. The open proximal end 22 of thehollow body 20 provides a device-receiving space 40 for receiving atleast the shaft 34 of the tissue-penetrating medical device 30. Thecover 12 includes at least one magnet 50, and in the embodiment show, atleast two magnets 50 disposed on the sleeve member 14.

The device-receiving space 40 is sized and shaped to permit movement ofthe shaft 34 of the tissue-penetrating medical device 30 into and out ofthe device-receiving space 40. In one embodiment, the device-receivingspace 40 permits movement of the shaft 34 of the tissue-penetratingmedical device 30 into the device-receiving space 40 in a movement thatis parallel to the longitudinal axis of the shaft 34 oftissue-penetrating medical device 30. One or more magnets 50 aredisposed on the needle cover such that one face of the magnet is exposedto the interior of the receiving space 40 in order to magnetize aportion, e.g. shaft 34 of the tissue-penetrating medical device 30,while the opposite face of the magnet is exposed to the magnetic shield60 associated with the cover 12 that prevents the magnetized portion,e.g. shaft 34, of the tissue-penetrating medical device from adverselyaffecting the clinical environment when the cover 12 is placed over thetissue-penetrating medical device 30. The cover 12 passively magnetizesthe shaft 34 of the tissue-penetrating medical device 30 when the cover12 is removed from the shaft 34 of the tissue-penetrating medical devicethereby having a portion of shaft 34 being exposed to one or magnets 50which are oriented to be exposed to the interior of the receiving space40.

In one or more embodiments, tissue penetrating device 30 is notmagnetized prior to placement of the tissue penetrating device intocover 12. When the tissue penetrating device 30 is placed into thedevice-receiving space 40 of cover 12, any distal section of the tissuepenetrating device 30 that passes under the influences of the magnets 50are magnetized. In one or more embodiments, portions of the tissuepenetrating device 30 will be re-magnetized again when the cover 12 isremoved prior to use and portions of the tissue penetrating device 30pass under the one or more magnets 50 disposed within thedevice-receiving space 40 of cover 12, even if some section of tissuepenetrating device 30 were de-magnetized due to storage or exposure toexternal magnetic fields while in storage.

According to one embodiment, the magnetic shield 60 composed of one ormore shielding material may be spray-coated onto an exterior surface ofthe cover, as shown in FIG. 2A, or onto an interior surface of thecover, as shown in FIG. 2B, such that at least one face of magnet 50 isnot coated with shielding material to allow the un-coated face of atleast one magnet 50 to be exposed to a portion (e.g., a shaft 34) of atissue-penetrating medical device when located in receiving space 40. Inanother embodiment, the magnetic shield 60 composed of one or moreshielding material may be spray-coated onto an interior surface andexterior surface of the cover. In one or more embodiments, the magneticshield 60 composed of one or more shielding material may be spray-coatedonto an interior surface of the cover or an exterior surface of thecover to a thickness of 1/1000th of an inch to 1 inch. The thickness ofthe magnetic shield may depend on the desired purpose or application ofthe medical device.

In another embodiment, the magnetic shield 60 composed of one or moreshielding material may be insert-molded into the cover. Insert moldingcombines metal and thermoplastic materials, or multiple combinations ofmaterials and components into a single unit. Insert molding processestypically involve an injection molding process in which solid pellets ofraw material are melted and extruded into a mold—the plastic is thensolidified—and then the press opens and the molded parts are ejected.The component to be insert-molded is placed in the mold, either by hand,or by automation before the material is injected into the mold. Then, asthe material flows into features in the insert, the insert is anchoredmuch more securely than if it were assembled to a previously moldedcomponent.

According to one or more embodiments, the cover 12 may be molded from aplastic having conductive additives or magnetic additives. In oneembodiment, the cover 12 may be sterile and/or disposable.

In one or more embodiments, the shielding material may be a highlyconductive material, such as copper or copper spray. A highly conductiveshielding material will work in the presence of high frequencyelectromagnetic field. The varying magnetic field will generate eddycurrent within the conductor which would then cancel the magnetic field,preventing the magnetic field from reaching the magnetized region, thuspreventing the potential demagnetization of the permanent magnets in thecover.

In one or more embodiments, the shielding material may have a highmagnetic permeability. In one or more embodiments, the high magneticpermeability material may be iron, nickel, cobalt or an alloy orcompounds containing one or more of these elements. In one or moreembodiments, the high magnetic permeability material is comprised of analloy of nickel and iron metals. The high magnetic permeability materialmay be Permalloy (a nickel-iron magnetic alloy, typically having about80% nickel and about 15% iron and 5% molybdenum content) orferromagnetic metal coating. In one or more embodiments, the shieldingmaterial may be composed of a nickel-iron alloy having approximately 77%nickel, 16% iron, 5% copper and 2% chromium or molybdenum. In yetanother embodiment, the shielding material maybe composed ofapproximately 80% nickel, 5% molybdenum, small amounts of various otherelements such as silicon, and the remaining 12 to 15% iron. A highmagnetic permeability shielding material will work well in the presenceof static external magnetic fields. When an external static magneticfield is present near the magnetized region, the magnetic field line isdrawn within the magnetic shield due to its high permeability, thuspreventing the magnetic field from reaching the magnetized region,protecting the permanent magnets in the cover. Because the magneticfield generated by the permanent magnets in the cover and the magnetizedneedle are static, it is preferable to use shielding material with highmagnetic permeability to prevent the magnetized tissue-penetratingmedical device 10 from causing magnetic interferences to sensitiveequipment and devices in a hospital setting.

If both a high frequency electromagnetic field and static externalmagnetic fields are expected to be present, the magnetic shield canconsist of both highly conductive shielding material and high magneticpermeability material to block the external magnetic field from reachingthe magnetized region. In a specific embodiment, the magnetic shield 60includes a highly conductive material and a ferromagnetic metal coating.The highly conductive material may be copper.

FIGS. 3A to 3C show a medical device 100 including a tissue-penetratingmedical device 130, a cover 112 for magnetizing the shaft 134 of thetissue-penetrating medical device 130. The cover 112 includes a sleevemember 114 having a hollow tubular body 120 having a distal end 121 andan open proximal end 122 to form a protective closure over the shaft 134of the tissue-penetrating medical device 130, the sleeve member 114having a length L to cover the shaft 134 of the tissue-penetratingmedical device 130, the shaft 134 having a length L2 and a distal tip136. The open end 122 of the hollow tubular body 120 provides areceiving space 140 for receiving at least the shaft 134 of thetissue-penetrating medical device 130. Cover 112 includes two magnets150 and a magnetic shield 160 that minimizes any effects to the clinicalenvironment from magnetic fields generated from the two magnets 150within the cover. It will be understood that while two magnets 150 areshown, the device is not limited to a particular number of magnets or toa particular location of the magnets around the sleeve member. Magnets150 may be positioned in any position or orientation around the sleevemember. In one or more embodiments, a single magnet can be utilized tomagnetize the shaft 134, or more than two magnets can be utilized.Magnetic shield 160 composed of one or more shielding materials may bespray-coated onto an interior surface of the cover 112 or an exteriorsurface of the cover 112 such that at least one face of magnet 150 isnot coated with shielding material to allow the un-coated face of atleast one magnet 150 to be exposed to a portion (e.g., a shaft 134) of atissue-penetrating medical device 130 when located in receiving space140. In one or more embodiments, the magnetic shield 160 composed of oneor more shielding materials may be spray-coated onto an interior surfaceof the cover or an exterior surface of the cover to a thickness of1/1000th of an inch to 1 inch. The thickness of the magnetic shield 160composed of one or more shielding materials may depend on the desiredpurpose or application of the medical device. In another embodiment, themagnetic shield 160 may be insert-molded into the cover.

In embodiments in which two magnets are utilized, the orientation of themagnetic fields of the two magnets can vary. One magnet can have northand south poles on axis with shaft of the tissue-penetrating medicaldevice, while the second magnet can have north and south poles off-axisor perpendicular to the shaft of the tissue-penetrating medical device.Alternatively, the two magnets both can have north and south poles offaxis with the shaft of the tissue-penetrating medical device, or the twomagnets both can have north and south poles on axis with the shaft ofthe tissue-penetrating medical device.

FIG. 3A shows the tissue-penetrating medical device 130 prior toinsertion into the cover 112 of the present disclosure. The tissuepenetrating medical device 130 includes the shaft 134 having a lengthL2, a distal tip 136, and the shaft 134 is mounted to the housing 130 bya hub 152. In one or more embodiments, the hub 152 includes a hub magnet155. In one or more embodiments, hub magnet 155 is a permanent fixedmagnet. Hub magnet 155 may provide for a fixed magnetic reference pointwhen the tissue-penetrating needle is used with a combination ofultrasound and magnetic technologies to provide visualization ofsubdermal anatomy and device position. FIG. 3B shows the shaft 134 ofthe tissue-penetrating medical device 130 partially inserted into acover 112 of the present disclosure. FIG. 3C shows the shaft 134 of thetissue-penetrating medical 30 device fully inserted into a cover 112 ofthe present disclosure. The medical device 100 as shown in FIG. 3C canbe packaged and ready for use for a medical procedure. The medicaldevice 100 shown in FIG. 3C can be packaged together with other devicesas part of a larger medical device assembly. Thus, FIG. 3C shows amedical device 100 which is a needle subassembly having a cover 112having at least one magnet 150 configured to magnetize shaft 134 of themedical device 100 upon removal of the cover 112 from the shaft. Themedical device 100 could further be packaged as part of a catheterassembly including a catheter adapter subassembly.

Depending on the magnetized region of the medial device, the magneticshield may be in the form of or incorporated into a needle cover,individual catheter wrapper, catheter dispenser, product packaging or acatheter shipper.

When the magnetic shield is incorporated into individual medical devicepackaging, the entire packaging can be coated with the magneticshielding material. Alternatively, only the sections of the packagingenclosing the magnetized regions may contains the magnetic shieldingmaterial. Such approach would facilitate ease of sterilization throughthe packaging.

FIG. 4 shows an embodiment with a magnetized needle ready for insertionafter cover 112 has been removed. This allows the device to be used withthe procedural guidance systems that utilize magnetic sensors as a meansof measuring and predicting needle tip location relative to the targetanatomy.

As shown in FIG. 4, the tissue-penetrating medical device 130 with theshaft 134 magnetized after the shaft 134 has been removed from theneedle cover shown in FIGS. 3B-3C. As shown in FIGS. 3B-3C, two magnets150 can be integrated into cover 112 so that the cover 112 passivelymagnetizes the shaft 134 upon removal of cover 112. The embodiment shownin FIGS. 3B-3C shows two magnets 150 positioned around cover 112. Such acover could be easily integrated in existing catheter assemblies andother invasive medical devices such as guidewires and stylets to enablethe magnetization of the shafts of various invasive medical devices uponremoval of the cover to passively magnetize the shaft. The axialposition of the magnets can be modified and positioned relative to theshaft length and the desired portion of the shaft to be magnetized. Forexample, in the case of a needle, the magnets can be specificallypositioned based on the gauge and length of the needle. As shown in FIG.3B, the positioning of the magnets would result in the shaft 134 beingmagnetized from the approximately the position P shown in FIG. 3C to thedistal tip 136 of the shaft 134 as the portion of the shaft from P tothe distal tip will be moved through the magnetic field provided by themagnets 150. This the tissue-penetrating medical device 130 can now beused with a procedural guidance system that utilize magnetic sensors asa means of measuring and predicting needle tip location relative to thetarget anatomy. In one or more embodiments, the distal end of the tissuepenetrating medical device 130 includes a notch 137 located on thedistal tip 136 of the shaft 134 to provide immediate confirmation ofvessel entry at a point of insertion. In one or more embodiments, themagnetized portion of the tissue-penetrating medical device may comprisea partial length of the tissue-penetrating medical device. In one ormore embodiments, the magnetized portion of the tissue-penetratingmedical device may comprise a distal tip of the tissue-penetratingmedical device. In one or more embodiments, the magnetized portion ofthe tissue-penetrating medical device may comprise an entire length ofthe tissue-penetrating medical device.

FIG. 5 shows an embodiment of a tissue-penetrating medical device 230including a cover 212 having a magnetizing collar 260, which can be amagnet in the shape of the collar 260 as shown. Magnetic shield 265composed of one or more shielding materials may be spray-coated onto anexterior surface 261 of the collar 260 such that the interior surface262 is not coated with shielding material to allow the un-coatedinterior surface to be exposed to a portion (e.g., a shaft 234) of atissue-penetrating medical device 230 is located in receiving space 240.In one or more embodiments, the magnetic shield 265 composed of one ormore shielding materials may be spray-coated onto exterior surface 261of the collar 260 to a thickness of 1/1000th of an inch to 1 inch. Thethickness of the magnetic shield 265 may depend on the desired purposeor application of the medical device. The cover 212 includes a sleevemember 214 having a hollow tubular body 220 having a distal end 221 anda proximal end 222 to form a protective closure over the shaft 234 ofthe tissue-penetrating medical device 230. The open end 222 of thehollow tubular body 220 provides a receiving space 240 for receiving atleast the shaft 234 of the tissue-penetrating medical device 230. Themagnetizing collar 260 is show as being disconnected from the cover 212,but the magnetizing collar 260 is variably positioned along the lengthL3 of the cover 212 relative to the shaft 234. The magnetizing collar260 can be used as a single use disposable item, or the magnetizingcollar 260 may be reusable since the needle cover stays in place duringthe magnetization step. Therefore, according to one or more embodiments,the magnetizing collar 260 is detachably mounted to the cover 212. Inalternative embodiments, the magnetizing collar 260 is permanentlymounted to the cover 260. The magnetizing collar 260 can be slidablymoved along the length of the cover 212. In other embodiments, thelength L4 of the magnetizing collar 260 may be equal to the length L3 ofthe cover 212 such that the entire shaft 234 of the tissue-penetratingmedical device 230. In other embodiments, the length L4 of themagnetizing collar 260 is 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80% or 90%of the length L3 of the cover 212. The magnetizing collar 260 can be atubular magnet that substantially surrounds the periphery of the cover,or the magnetizing collar 260 can be a cover made of plastic or othermaterial with an array of magnets substantially surrounding theperiphery of the cover.

FIGS. 6A-6C show one way of integrating at least one magnet with a coverfor a tissue-penetrating medical device. According to one or moreembodiments, as shown in FIG. 6A the cover 312 may have a wall 360 madeentirely of a magnetic shielding material wherein one or more magnets350 are disposed in slots 362 positioned on the interior surface of thereceiving space 340 around the sleeve member. In one or moreembodiments, the slots 362 are positioned around the sleeve membersurround the device-receiving space 340. In one or more embodiments, themagnetic shield composed of one or more shielding material surrounds aportion of the one or more magnets disposed inside the sleeve member. Inone or more embodiments, the magnetic shield composed of one or moreshielding material surrounds the exterior surface of the sleeve member.In one or more embodiments, the magnetic shield composed of one or moreshielding material surrounds the interior surface of the sleeve suchthat the one or more magnets disposed inside the sleeve member areexposed to the receiving space of the sleeve member.

FIG. 6A shows a partial perspective view and FIG. 6B shows an end viewof a cover 312 having an embedded magnetic 350 in the wall 360 of thecover 360 having a magnetic shield 365 comprised of magnetic materialalong the exterior surface of wall 360. The magnet 350 is embedded in aslot 362. The magnet 350 can be sized to be slidably mounted within theslot 362 and held in place by friction fit, or the magnet can beattached with an adhesive or other suitable ways. Alternatively, themagnet 350 could be integrally molded into the wall 360 during theforming process for the cover 312. The length L5 of the magnet 350 shownin FIG. 6A is shown as being less than the length of the cover.According to one or more embodiments, the length L5 of the magnet 350can be equal to the length of the cover, or 10%, 20%, 30%, 40%, 50%,60%, 70%, 80% or 90% of the length of the cover.

FIG. 6C shows an embodiment of a cover 412 with a first magnet 450 in afirst slot 462 of the wall 460 of the cover 412, and a second magnet 452in a second slot 464 in the wall 460 of the cover. The first magnet 450and second magnet 452 are shown as being positioned around the cover412, for example, 180 degrees from each other. It will be understoodthat the two magnets can be in other positions with respect to eachother. Additionally, the cover 412 can include more than two magnets.The first magnet 450 and second magnet 452 can be slidably mounted inthe respective first slot 462 and the second slot 464 and held in placeby friction fit, or they could be held in place by adhesive. Inalternative embodiments, the magnets can be integrally molded with thecover 412. The two or more magnets may have oppositely oriented poles.As an exemplary embodiment, magnetic shield 465 is shown comprised ofmagnetic material along the interior surface of first slot 462 and thesecond slot 464.

In alternative embodiments, a needle cover is provided that hasgeometric dimensions that permit the needle cover to be placed insideexisting needle magnetizing devices while the needle cover is coveringthe shaft of the needle. The distal end of the needle cover may be usedto limit the depth of insertion by providing a stop to contact thebottom of the needle magnetizing device. Alternatively, a feature nearthe proximal portion of the needle cover can be provided on the cover tolimit the depth of insertion by a stop on the proximal opening of theneedle magnetizer.

The covers described herein can have a variety of properties. In one ormore embodiments, the covers are formed from plastic. In one or moreembodiments, the covers are sterile. In one or more embodiments, thecovers are disposable. In other embodiments, the covers may be bothsterile and disposable.

The tissue-penetrating medical device may be a needle, catheter,introducer needle, stylet, scalpel or guidewire. In one embodiment, thetissue-penetrating medical device is a needle, which when magnetized canbe used with a procedural guidance system to locate and project theposition of the needle during an invasive medical procedure. Thetissue-penetrating medical device according to one or more embodimentsis includes a magnetizable metallic material. In a specific embodiment,the magnetizable metallic material is magnetizable stainless steel.

The covers described herein may also be incorporated into a vascularaccess device comprising a catheter, a catheter adapter subassembly, anda needle subassembly including an introducer needle, a needle hubconnected to the proximal end of the introducer needle and a needlecover according to any of the embodiments described herein. The needlecover may include a plastic sleeve member having a hollow tubular bodyto form a protective closure over the introducer needle, and two or moremagnets disposed on the needle cover as described herein.

An example of a medical device assembly, specifically a vascular accessdevice including a catheter according to any of the foregoingembodiments described above is illustrated in FIG. 7. The medical deviceassembly 500 shown in FIG. 7 comprises a tissue penetrating medicaldevice in the form of a needle subassembly 514, and a catheter adaptersubassembly 512 including a catheter adapter body 516 and a cathetertubing 518 and a permanent magnet element 532, a cover 530 having anembedded magnetic 535 in the wall of the cover 530 having a magneticshield 565 comprised of magnetic material along the exterior surface ofwall. FIG. 8 shows a partial exploded view of the embodiment of amedical device shown in FIG. 7 having a magnetic field 515 containedwithin the cover having a magnetic shield 530. In one or moreembodiments, the catheter adapter is connected to the proximal end ofthe shaft.

A permanent magnet element located along the introducer needle may serveas an additional reference point when used in combination withultrasound and magnetic technologies to provide visualization ofsubdermal anatomy and device position. A needle 519 within the cathetertubing 518 shows a cover 530, and the needle has been magnetized uponremoval of a cap including a magnet as described with respect to FIGS.2-7 herein. Magnetizing the needle with the cover as described hereincreates a magnetic field in the magnetic region.

The medical device 500 may be a vascular access device which includes alateral access port 556 and may be connected to a section of anextension tube 560 for establishing fluid communication between an IVfluid source and the catheter tubing 518. In one or more embodiments,the extension tube 560 is built-in to reduce contamination andmechanical phlebitis by eliminating manipulation at the insertion site.In one or more embodiments, the extension tube 560 is compatible withhigh pressure injection. In one or more embodiments, the extension tube560 provides continuous confirmation of vessel access during advancementof the catheter into the patient vein.

In one or more embodiments, a needle of a needle subassembly 514 isinserted into a lumen of the catheter tubing 518. The needle subassembly514 is shown as including finger grips 584 positioned at the sides ofthe needle subassembly 514 to facilitate various insertion techniques.In one or more embodiments, bumps may be present on the finger grip toindicate where to the user may grip the device for needle removal. Inone or more embodiments, a thumb pad 585, having a gently convexsurface, is provided at the proximal end of the needle subassembly 514.A flange 586, having a gently convex surface, is provided at theproximal end of the needle subassembly 514 to provide a finger pad. Awing member 570, thumb pad 585 and flange 586 may be utilized by theuser during insertion, permitting the user to elect which insertiontechnique to employ.

In one or more embodiments, the needle subassembly 514 includes a needleshield 580. The needle shield 580 may be a design adapted to secure thetip of the needle within the shield after use. In one or moreembodiments, the needle shield 580 may be activated passively. Theneedle tip is completely covered by the needle shield 580 in a fixedposition. In one or more embodiments, a ferrule, crimp or otherstructure may be included near the tip for engagement with a needleshield in certain applications.

A push tab 581 may be provided to facilitate catheter advancement duringinsertion. The push tab 581 also allows for one-handed or two-handedadvancement. In one or more embodiments, the push tab 581 is removedwith the needle shield 580. A clamp 582 may also be included on theextension tubing to prevent blood flow when replacing the access port.

In one or more embodiments, the vascular access device 500 furtherincludes a first luer access 572 and a second luer access 573 in fluidcommunication with the extension tube 560, a blood control split septum574 associated with the first luer access 572, and an air vent 576associated with the second luer access 573. Split septum 574 allows fora reduction in catheter-related bloodstream infection (CRBSI) whileproviding unrestricted flow and a straight fluid path and functions as ablood control septum. In one or more embodiments, the split septum 574may be located in an internal cavity of the catheter adapter or on thedistal end of the catheter adapter. In yet another embodiment, the splitseptum 574 may be located on a distal end of the extension tube 560. Theair vent 576 allows air to escape from the system during insertion,providing continuous confirmation of vascular access while preventingleakage of blood from the system during insertion. In one or moreembodiments, the air vent 576 may be at the distal end of extension tube560.

In one or more embodiments, the base unit can be integrated into theultrasound system with the ultrasound processor and a magnetometricdetector being in direct communication with the ultrasound system eithervia wireless link or using the same physical cable.

Another aspect of the disclosure pertains to a method of magnetizing atissue-penetrating medical device. Embodiments of the method includepositioning a shaft of the tissue-penetrating medical device into acover having a device-receiving space, at least one magnet disposedwithin the device-receiving space, and a magnetic shield composed of oneor more shielding materials associated with the cover; and subsequentlyremoving the tissue-penetrating medical device from the device-receivingspace to magnetize the shaft of the tissue-penetrating medical device.

Reference throughout this specification to “one embodiment,” “certainembodiments,” “one or more embodiments” or “an embodiment” means that aparticular feature, structure, material, or characteristic described inconnection with the embodiment is included in at least one embodiment ofthe disclosure. Thus, the appearances of the phrases such as “in one ormore embodiments,” “in certain embodiments,” “in one embodiment” or “inan embodiment” in various places throughout this specification are notnecessarily referring to the same embodiment of the disclosure.Furthermore, the particular features, structures, materials, orcharacteristics may be combined in any suitable manner in one or moreembodiments.

Although the disclosure herein has provided a description with referenceto particular embodiments, it is to be understood that these embodimentsare merely illustrative of the principles and applications of thepresent disclosure. It will be apparent to those skilled in the art thatvarious modifications and variations can be made to the method andapparatus of the present disclosure without departing from the spiritand scope of the disclosure. Thus, it is intended that the presentdisclosure include modifications and variations that are within thescope of the appended claims and their equivalents.

What is claimed is:
 1. An assembly comprising: a tissue-penetratingmedical device having a distal tip, a housing, and a shaft mounted tothe housing by a hub, the hub including a hub magnet; and a cover formagnetizing the tissue-penetrating medical device, the cover including asleeve member having a hollow body with an exterior surface, an interiorsurface, a proximal end, and a distal end to form a protective closureover a shaft of a tissue-penetrating medical device having alongitudinal axis, the proximal end of the hollow body providing areceiving space for receiving at least a shaft of the tissue-penetratingmedical device; one or more magnets disposed along the sleeve membereffective to magnetize the shaft; and a magnetic shield composed of oneor more shielding materials spray-coated onto the sleeve member, a firstface of the one or more magnets being exposed to the receiving space andan opposite face of the one of one or more magnets being exposed to themagnetic shield.
 2. The assembly of claim 1, wherein the receiving spacepermits movement of the shaft of the tissue-penetrating medical devicein the receiving space in a direction parallel to the longitudinal axisof the tissue-penetrating medical device.
 3. The assembly of claim 1,wherein the receiving space permits movement of the shaft of thetissue-penetrating medical device into and out of the receiving space.4. The assembly of claim 1, wherein two or more magnets are disposedalong the interior surface of sleeve member.
 5. The assembly of claim 1,wherein the one or more shielding material is a highly conductivematerial.
 6. The assembly of claim 5, wherein the one or more shieldingmaterial comprises copper.
 7. The assembly of claim 1, wherein the oneor more shielding material has a high magnetic permeability.
 8. Theassembly of claim 7, wherein the one or more shielding materialcomprises an alloy of nickel and iron metals.
 9. The assembly of claim8, wherein the one or more shielding material includes a ferromagneticmetal coating.
 10. The assembly of claim 1, wherein the one or moreshielding material includes a highly conductive material and includes aferromagnetic metal coating.
 11. The assembly of claim 10, wherein thehighly conductive material comprises copper.
 12. The assembly of claim1, wherein the one or more shielding material is spray-coated onto anexterior surface of the cover.
 13. The assembly of claim 1, wherein theone or more shielding material is spray-coated onto an interior surfaceof the cover.
 14. The assembly of claim 1, wherein thetissue-penetrating medical device is a needle assembly, a stylet,catheter, introducer needle, scalpel or guidewire.
 15. The assembly ofclaim 1, wherein the one or more magnets comprises a fixed permanentmagnet.
 16. The assembly of claim 1, wherein the hub magnet comprises afixed permanent magnet.
 17. The assembly of claim 1, wherein theshielding material may be insert-molded into the cover.
 18. The assemblyof claim 1, wherein the shaft of the tissue-penetrating medical devicecomprises a magnetizable metallic material.
 19. The assembly of claim 1,wherein the shielding material is spray-coated to a thickness of1/1000th of an inch to 1 inch.